PVC terrmite controle works quite well, also termite barriers, it's a cloth that is placed in the concrete wherever anything perferates it, works even better. Termites live in the soil, not in the wood and migrate to there food sorce on a daily basis, so if you can get in your crawl space make it a quartly scedual to go under the house and inspect for any termite tunnels. They are usually easilly visable as dirt tunnels on your concrete. If you find even one call the exterminators. If you do this regularly you won't have any problems. If you have the exterminators do the inspection you will "of course" always have a termite infestation, so you have to do it yourself.